1. Field of the Invention
The present invention relates to a steering wheel mounting assembly for mounting a steering wheel to a steering shaft.
2. Description of Related Art
A steering wheel comprises an annular ring member, a pad member disposed in the center of the ring member, and spoke members for connecting the ring and pad members. A ring core is embedded in the ring member and so are spoke cores in the respective spoke members. In this case, the ring and spoke cores are covered with a covering material such as foamed urethane. Further, a boss plate for securing a steering shaft is coupled to the spoke cores beneath the pad member.
On the other hand, there has recently been proposed a steering wheel free from the boundary line between the covering material and the pad member by integrally forming the covering material and the pad member for improvement in design (e.g., Japanese Utility Model Publication No. Hei. 2-133955).
The aforementioned steering wheel has been increasingly used for improvement in design. However, there has been a problem in that it is difficult to tighten the nut of the boss plate from above such that the boss plate is coupled to the spoke cores, since the pad member is not removable from the covering material used for the ring and spoke cores. Therefore, there has developed a demand for a new mounting assembly ensuring that a steering wheel is readily mounted onto its steering shaft even in such a state that a boss plate has been coupled to spoke cores, that is, the steering wheel has been assembled completely.
The number of serration teeth formed on the steering wheel or steering shaft side may vary depending on the specification requirements. Even in such a case, however, there is still a persistent demand for reduced cost steering-wheel mounts without, for example, requiring significant or any design changes.